3 Exposure
3.1 Introduction
Workers may be exposed to CCP or its components during handling or manufacturing. This chapter summarizes exposures from CCP handling reported in the literature (Table 3–1). Little consistency exists among these reports: they vary depending on the chemical composition of the CCP, the method of manufacturing during the study period, and the number of forms handled during the industrial hygiene survey. For workers who handle CCP, the most common exposures are to formaldehyde and kerosene or its components. Formaldehyde is used in some microcapsule manufacturing processes as part of the mixture that forms the shell for the microcapsules; it is also used in the manufacture of other paper products such as plain bond paper. Kerosene is one of the principal solvents used to solubilize the precursor dyes contained in the microcapsules.
3.2 Exposure Data
3.2.1 Published Studies
Some studies listed in this section are described in another section of this review.
Jujo Paper Company, Ltd. 1979. One of the earliest reports with CCP exposure data came from the Jujo Paper Company, Ltd. [1979]. They reported that the maximum concentration of CCP solvent (unspecified) in a finishing room where 100 tons of CCP were handled each day was 0.3 mg/m3. The company also reported an average CCP solvent retention of 180 μg on the fingers of women who handle, sort, and count 50,000 to 70,000 sheets each day. Blood samples obtained 15 to 16 hr after work revealed no detectable concentrations of the solvent. Further biochemical tests of the blood and urine, skin tests (types unspecified), examinations, and interviews of 135 exposed workers and 84 comparison workers revealed no differences between the two groups. The company indicated that no skin disorders had been reported by any worker since the CCP mill came into operation. No independent survey of worker complaints was performed.
Mølhave and Grunnet 1981. In an addendum to the telephone company report by Menné et al. [1981], Mølhave and Grunnet [1981] reported on a headspace analysis (sampling of the gaseous phase of a sample heated to 50 °C) of the CCP in use at the time of the study. They used one paper sample received from the factory where the problem was investigated and one sample from the manufacturer of the paper. The authors reported that more than 42 chemicals degassed from the paper samples, and concentrations were seven times greater in the paper from the facility than in those of the manufacturer's sample. About 90% of the emission was alkanes or alkenes (C5–C14). Another analysis was performed on the Santosol oil content of both CCP samples. The CCP that (according to the authors) caused the original skin problems contained up to 150 times the amount of Santosol oil contained by the manufacturer's sample of CCP. According to the authors, the Santosol oil consists
